62 results about "Static displacement" patented technology

The invention discloses a quasi-zero stiffness vibration isolator based on a transverse groove spring, and belongs to the field of vibration isolators. An existing linear vibration isolator cannot simultaneously achieve a wide vibration isolation frequency band and small static displacement. According to the quasi-zero stiffness vibration isolator based on the transverse groove spring, a balance position adjustment structure is arranged on the upper surface of a bottom plate of a supporting frame; a positive stiffness mechanism is arranged on the upper part of the balance position adjustment structure; and the periphery of the positive stiffness mechanism is connected to the inner wall of a side face plate of the supporting frame through a set of negative stiffness mechanisms, and the twoends of the negative stiffness mechanisms are connected with the positive stiffness mechanism and the inner wall of the side face plate of the supporting frame through rotating pairs correspondingly.The dynamic stiffness at the balance position is zero, the vibration isolation performance for ultra-low frequency vibration is improved, and the effect of full frequency band isolation can further beachieved especially for basic excitation.

The invention relates to a three-dimensional small surface element magnetotelluric continuous array data acquisition method for improving the acquisition quality in oil geophysical prospecting. The method comprises the steps: each acquisition station simultaneously begins to acquire and record time series data of a natural electromagnetic field when a small surface element grid is adopted to acquire and record for construction and electrode distribution, and a diagonal point and a center point respectively carry out addition and work out average value to the same weight of two adjacent points to all points of time domain electric filed data of all observation points by taking a recording point as a center; an angular point calculates the average value of the weights of the same electric field of two adjacent points and all measuring points towards the surface element; the calculated electric field weights of the maximum space are respectively used as new observation field values; new time series data for compressing noise and static displacement effect is obtained, and the apparent resistivity and the phase curve of each point can be obtained through processing by a conventional method. The invention compresses the noise and static displacement effect and obviously improves the MT data acquisition in areas with serious noise interference and static displacement.

The invention relates to a displacement control method for a hub motor fluid power system variable pump, and belongs to an automobile control system. The revolving speed of front wheels follows the revolving speed of rear wheels. The displacement control method is mainly divided into static regulation and PI (proportional integral) regulation, wherein the static regulation comprises two steps of gear estimation and displacement table search; the table is directly searched according to the estimated gear to obtain a constant value displacement, i.e. the static displacement; the PI feedback regulation of the difference value of the front wheel speed and the rear wheel speed needs to be added to correct the static displacement. The displacement control method for the hub motor fluid power system variable pump has the advantages that the front wheel speed and the rear wheel speed of the automobile can be consistent under the control of the control method when the system is under the auxiliary driving working condition, and the trackslip efficiency of the whole automobile is optimal while the hub motor fluid power system is controlled to obviously improve the passage capacity of the whole automobile on a low-adhering road surface or a road surface with a big slope.

The invention discloses a withstand high voltage eddy current displacement sensor comprising shell, skeleton winded with induction coil and short circuit ring with inner casing between them, inner shell is made of withstand high voltage nonpermeametion material and outer shell of soft magnetic material, induction coil winded by high strength wire is used to measure dynamic or static displacement. It has wide measuring range, good linearity, high mechanical strength and thermal stability, wide frequency response, extending limitation of traditional eddy current displacement sensor, so can be widely used in displacement measurement of valve core or hydraulic cylinder piston under high voltage.

An early warning method for abnormity of the whole lateral load resistance performance of a large-span bridge structure comprises the following steps that (1), data acquisition is carried out on the three-dimensional wind field and the GPS displacement effect of the midspan position of a main beam; (2), vector decomposition and mean processing are carried out on the collected data, and static wind speed sequences and static displacement sequences in the transverse direction of the bridge are obtained; (3), the static wind speed sequences and the static displacement sequences are divided according to months, and a main correlation sequence of the static wind speed sequences and the static displacement sequences on the same month is determined by the utilization of wavelet packet cross correlation coefficients; (4), Fourier series fitting is carried out on the main correlation sequences on all the months in sequence, and the abnormity of the whole lateral load resistance performance of the large-span bridge structure is warned easily by the utilization of the month change characteristics of the fitted parameter values. The early warning method for abnormity of the whole lateral load resistance performance of the large-span bridge structure based on the measured wind load effect makes up for the blank in the research on the aspect of the early warning of the abnormity of the whole lateral load resistance performance of the large-span bridge structure and can provide important reference for monitoring and analyzing the whole lateral load resistance performance of the large-span bridge structure.

The invention provides a soil body internal horizontal displacement test technology for underground structure vibration table testing, and belongs to the technical field of civil engineering. A magnetic bushing displacement meter comprises a polyvinyl chloride (PVC) bushing (2), a magnetic cutting ring (3) and a connecting line type magnetic probe (4), wherein the two ends of the PVC bushing (2) are open; the magnetic cutting ring (3) is a circular magnetic ring which is sleeved outside the PVC bushing (2); the magnetic probe (4) is cylindrical, one end of the magnetic probe (4) is provided with a guy line (5) and the other end of the magnetic probe (4) is connected with a measuring soft ruler (1); and the magnetic probe (4) is freely arranged at one end in the PVC bushing (2). The test technology for a soil body internal horizontal displacement field comprises a soil body horizontal static displacement field measuring technology and a horizontal displacement dynamic change measuring technology. The technology has the characteristics of simple structure, low cost, high reliability and easiness in implementation and maintenance, and is expected to be popularized in other similar tests or tests of an engineering soil body internal horizontal displacement field.

The invention provides a negative stiffness element with automatic balance position adjusting capacity and a negative stiffness property generation method and application, and relates to the field ofground-based simulation of gravity environment. The negative stiffness element with automatic balance position adjusting capacity and the negative stiffness property generation method and applicationare purposed to solve the problem of variation of mechanical property, caused by variable mass load, of a balance position of an existing high static and low dynamic stiffness supporting system; the dynamic stiffness of the new system is reduced on the premise that the original system balance position is not influenced so as to ensure that the stable balance position of the system in static loading process is the same as that of an original system; when dynamic load acts on the system, the system stiffness is the value of difference between the original system stiffness and the negative stiffness element stiffness. The geometric nonlinear property and adjustable geometric parameter property of a mechanism are utilized, the transverse spring stiffness and the effective length of a roller mechanism are properly set to realize the special negative stiffness property; a mechanism housing and a central vertical column are locked and unlocked to realize the negative stiffness property of opening and closing elements in a special condition. Therefore, the problems that the static displacement beyond the limit due to excessively low system stiffness or the mechanical property of a balancepoint of a quasi-zero stiffness system is damaged due to excessively low system stiffness can be avoided.

The new type of displacement meter includes laser source and laser range finding assembly for ranging; suspension system to make the laser source in suspension state; and signal processing unit to process measuring signal and display or output. The laser source, the laser range finding assembly and the suspension system are set inside one casing, and the measuring output of the laser range finding assembly is connected to the signal processing unit. Owing to the suspension technology and the laser ranging technology, the present invention measures the absolute displacement amount in the nanometer level precision, and has no phase shift variation, flat frequency response in wide frequency range, capacity of measuring static displacement, powerful anti-jamming capacity and high stability. The present invention may find its application in many fields.

The invention relates to the technical field of rail transit, in particular to a novel method for calculation of a dynamic envelope line of a railway vehicle. The method includes: firstly, determining 3 calculation sections on a vehicle body, and setting observation points, same in serial number and position, on the sections respectively; secondly, on the basis of a vehicle / rail coupling dynamic model, comprehensively considering influences of vehicle and rail participant vibration to quickly determine dynamic displacement of the observation points of the three calculation sections; thirdly, as for the observation points with same serial numbers, taking a maximum value of the dynamic displacement of the 3 calculation sections; finally, drawing the dynamic envelope line of the whole vehicle running on a rail according to an original coordinate value of each observation point and corresponding maximum dynamic displacement and static displacement. Compared with a traditional method for calculation of the dynamic envelope line of the railway vehicle, the novel method has the advantage that objective facts can be represented better to provide scientific theoretical basis and specific implement directions for calculation of dynamic envelope lines of railway vehicles.

The invention discloses a communication iron tower perpendicularity problem judgment method and system based on the Internet of Things. The system comprises a regular data acquisition and storage module, a data extraction and inclination angle change value and inclination angle absolute value calculation module, a dynamic displacement judgment module and a perpendicularity judgment module, wherein the regular data acquisition and storage module regularly detects inclination angle data of an iron tower and transmits the data to a system for storage through an inclination angle sensor on the iron tower; the data extraction and inclination angle change value and inclination angle absolute value calculation module calculates related data through formulas; the dynamic displacement judgment module judges whether the iron tower has dynamic displacement or not according to average inclination angle change values; the perpendicularity judgment module judges whether the iron tower has the perpendicularity problem according to inclination angle absolute value data under static displacement. The method and the system solve the technical problems of low accuracy and efficiency of manual detection and judgment of perpendicularity of the communication iron tower.

The invention relates to a piezoelectric transducer for detecting static displacement and method therefor, belonging to the field of the piezoelectric transducer. The piezoelectric transducer for detecting the static displacement comprises an organic film, and piezoelectric ceramic pieces arranged at the two sides of the organic film; a PCB to be detected is stuck on one piezoelectric ceramic piece, and inverse piezoelectric effect of the piezoelectric ceramic pieces can be utilized to generate driving force, so that the piezoelectric ceramic pieces arranged at the other side of the organic film can generate a certain electrical signal output under the piezoelectric effect; meanwhile, continuous external force is applied on the PCB, and different electrical signal outputs can be generated when the PCB has tiny deformation, and the electrical signal can be detected out by an oscilloscope. The piezoelectric transducer has simple and reliable structure and low cost, and the detection method is simple and practical, so that the invention can be widely applied to industrial production.

The invention provides a double light source sinusoidal phase-modulation displacement measurement interferometer, which is suitable for measuring a static displacement. The interferometer comprises a light source, an optical fiber coupler, an isolator, a collimator, a photoelectric detector and a signal processor, wherein the light source is provided with driving power supplies and a temperature controller, and has different wavelengths; a trigger controller with the same initial phase is connected between the two driving power supplies; the photoelectric detector converts a received interference signal into an electric signal and then inputs the electric signal to the signal processor; other two input ports of the signal processor are respectively connected with the two driving power supplies; and a data processed by the signal processor is displayed on a digital display. Compared with the prior art, the interferometer of the invention has the advantages of having simple structure and no optical element, theoretically eliminating the error of a measured result caused by ignoring light intensity modulation of the light source through reasonable selection of depth of sinusoidal phase modulation, and promoting the measuring precision.

The invention discloses a method for identifying elastic parameters of fibers and a matrix of a composite after molding, comprising the following steps: S1, building a microscopic model of the composite, carrying out static structural analysis on the microscopic model by adopting a finite element method, extracting static displacement data, and calculating relative sensitivity of a static displacement field on the elastic parameters of the fibers and the matrix; and S2, taking 2-norm of displacement residual errors of a test and finite element simulation as a target function, and minimizing the target function by utilizing an iterative optimization algorithm. The method disclosed by the invention provides a composite microscopic model considering properties of component materials, carriesout relative sensitivity analysis on parameters of the component materials by virtue of structural displacement responses, identifies the elastic parameters of the fibers and the matrix of the composite after molding by adopting the iterative optimization algorithm and has great significance in engineering.

The invention discloses a magneto-telluric field static displacement correcting method based on an inversion model, and belongs to the technical field of data processing of a telluric electromagnetic sounding method. The correcting method comprises the following steps that a high resistance body or a low resistance body with a shallow copy assigned to generalized static displacement electrical resistivity is added in a designed inversion initial model, in other words, the model grid electrical resistivity corresponding to a measurement point with static displacement is assigned to the generalized static displacement electrical resistivity to participate in inversion, accordingly, the static displacement of the measurement point is corrected, and the inversion result with the static displacement correction effect is obtained. The resistivity of the high resistance body is larger than that of the background, and the resistivity of the low resistance body is smaller than that of the background. According to the correcting method, the magneto-telluric field static displacement correcting is carried out on the basis of a three-dimensional theory, the corrected result is closer to the actual underground electrical structure, and information is more accurate. The static displacement correcting is achieved by designing the original model, the static correction implementing complexity is lowered, and zero-cost working is achieved.

The invention provides a method for dynamically monitoring a vertical displacement of a building. The method comprises the following steps: determining a boundary fd of a low-frequency displacement and a dynamic displacement according to the lowest response frequency of a vertical acceleration sensor, the frequency smaller than or equal to fd as the low-frequency displacement, and the frequency greater than fd as the dynamic displacement; obtaining the displacement of a measurement point relative to a reference point by a liquid pressure difference measured by a liquid pressure sensor, and measuring a static displacement and the low-frequency displacement after low-pass filtering; obtaining a displacement spectrum from the acceleration measured by the acceleration sensor after fourier transform and high-pass filtering according to the relation between the acceleration spectrum and the displacement spectrum; finally obtaining the dynamic displacement by inverse fourier transform; and adding the static displacement, the low-frequency displacement and the dynamic displacement to obtain the vertical displacement. By adopting the method provided by the invention, the static displacement, the low-frequency displacement and the dynamic displacement are respectively measured by adopting two different methods; an error is effectively reduced; meanwhile, the method is fewer in demands on the field, wide in application range and convenient to use.

The invention relates to a method for realizing structural contact force optimization by adopting equivalent static displacement, belonging to the field of engineering structure optimization design. The main steps are as follows: firstly, the nonlinear contact analysis of the structure is carried out to obtain the contact force of the joint on the contact surface; secondly, the contact force is applied as a static external load on the node of the original contact surface, and its static displacement is calculated; finally, the static displacement is applied to the node of the contact surface as a constraint of forced displacement, and the constraint reaction force under the linear static condition is optimized. If the optimized structure meets the contact force constraint requirements, theoptimization is stopped, otherwise the above steps are repeated. The invention can rationally optimize the structure involving the contact force and avoid the structural designer from relying excessively on the sensible engineering experience. Compared with the traditional surrogate model method, this method has higher optimization accuracy and less computation, and can be applied to complex engineering problems.

The invention discloses a multi-node super-long deep part displacement monitoring system based on the RS485 bus technology.The multi-mode super-long deep part displacement monitoring system comprises N multi-mode acceleration sensor units, N 485 digital relay control units and a wireless data collecting and transmitting device, wherein N is larger than 1.The acceleration sensor units and the 485 digital relay control units are connected through 485 buses.All point positions and layer positions of deep drilling are subjected to three-dimensional static displacement measurement, N 485 digital relays control the N multi-mode acceleration sensor units in a matched mode to ensure that the current of a power supply circuit can be switched on and switch off in sequence through all the units, the current is transmitted to all acceleration sensors in sequence to the tail end of the whole string of sensors, and thus the 485 buses can be used in sequence.According to the multi-node super-long deep part displacement monitoring system and a monitoring method, deep displacement can be captured for a long term for deformation measurement, installation is easy and convenient, manufacturing cost is low, the monitoring system and the monitoring method are suitable for the situation of China and wide application, and great significance is achieved on monitoring and early-warning of geological disasters.

The invention discloses equipment for evaluating the static displacement and deformation of a vibration insulating foundation of a steam-turbine generator, and belongs to the technical field of design of a spring vibration insulating foundation of the steam-turbine generator. The equipment comprises a finite element analysis module, a parameter calculation module, a result evaluation module and an output module, which are sequentially connected and perform processing by utilizing a computer system. The invention also discloses a method for evaluating the static displacement and deformation of the vibration insulating foundation of the steam-turbine generator. According to the equipment, model data obtained by a foundation designer is delicately post-processed, key displacement and deformation indexes with great influence on the running of a machine set are extracted after calculation, and whether the static displacement and deformation of the vibration insulating foundation are qualified or not is evaluated. Moreover, the method can be easily implemented in mathematical calculation software such as Excel or Matlab, and is low in calculation requirement and high in operability.

The invention discloses a method for determining girder transverse static displacement of a long-span bridge structure. The method comprises the following steps that step (1) GPS displacement in a girder span and monitoring data of a three-dimensional wind field are collected; step (2) vector decomposition and mean processing are conducted on the monitoring data, and transverse static displacement and transverse static wind speed data are acquired; step (3) main correlative components of the transverse displacement intervened by the transverse static wind speed are fitted by the adoption of the 3-order Fourier series; step (4) discrete components of the transverse static displacement are fitted by the adoption of the mean - variance model; step (5) the fitting transverse static displacement of the girder members of the long-span bridge structure is determined. According to the method, a mathematical modeling method is adopted based on the monitoring data, and the transverse static displacement of the girder members of the long-span bridge structure can be more accurately determined.

The invention discloses a device for calibrating static and dynamic characteristics of a contact probe type contourgraph sensor. The device comprises a static displacement performing device, a dynamic displacement performing device and a displacement measuring device, wherein the static displacement performing device comprises a base, a right bearing seat, left bearing seat, a ball screw, an oblique block, an x-direction linear guide rail sliding block, a first linear guide rail, a second linear guide rail, a z-direction working table and a z-direction support frame. The oblique block is fixed on the x-direction linear guide rail sliding block, the sliding block is installed on the first linear guide rail, and the first linear guide rail is fixedly connected with the base. The ball screw penetrates through the center of the oblique block, and two ends of the ball screw are respectively fixed on the right bearing seat and the left bearing seat. The second linear guide rail is fixed on an oblique plane of the oblique block. The z-direction working table is connected with the z-direction support frame, and the z-direction support frame is connected with the base. The z-direction working table and the second linear guide rail convert x-direction movement into z-direction movement through sliding friction. The device for calibrating the static and dynamic characteristics of the contact probe type contourgraph sensor has the advantages of being high in calibrating accuracy, large in calibrating range, high in calibrating speed, simple in structure and low in cost.

The invention discloses a method for using time domain transient horizontal electric field down step response to improve a resolution capability of an electrical layer. The method includes the steps of: (1) obtaining horizontal electric field record data of a magnetotelluric field time domain which are collected in field, thereby obtaining two electric field components in a horizontal direction; (2) performing superposition and filtering processing on the electric field components; (3) performing editing processing on up and down step electric field values of the electric filed components, and removing flying spots that deviate obviously; (4) calculating a horizontal electric field in a phi direction; and (5) calculating high-resolution apparent resistivity. The method provided by the invention overcomes the problem of static displacement existing when up step waveform processing is adopted, and greatly eliminates shallow layer interference information irrelevant to the electrical layer. Under the condition that the electrical resistivity of the upper player of electrical layer which is close to the earth surface is relatively small, electromagnetic waves are shielded, but by adoption of the method provided by the invention, electrical layering information with high resolution can still be obtained, thereby enabling an application range of time domain electromagnetism to be expanded.

The invention discloses a lifting belt-type suspender for horizontal hoisting and belongs to mechanical hoisting equipment. The lifting belt-type suspender solves the problem that the existing horizontal hoisting suspender has a limited adjustment or use range, low efficiency and poor universality. The lifting belt-type suspender comprises a hanging beam, lifting belts, front and rear rotating shaft assemblies and an overturn support. The two lifting belts are hung under left and right ends of the hanging beam. One end of each one of the two lifting belts is connected to the front rotating shaft assembly and the other end of each one of the two lifting belts is connected to the rear rotating shaft assembly. The front rotating shaft assemblies and the two rear rotating shaft assemblies are connected to the overturn support. The overturn support comprises four tripods. The lifting belt-type suspender has a simple structure, good versatility, high strength and good integrated mechanical properties. All the parts of the lifting belt-type suspender can be detachably connected so that manufacture and maintenance are simple and manufacturability is good. The lifting belt-type suspender can be used for horizontal hoisting of cabins having different quality, centroids and sizes and realize change of a static displacement state of the cabins under support action of the overturn support.

The invention relates to an electromechanical integrated low-frequency acoustic emission energy transducer. The electromechanical integrated low-frequency acoustic emission energy transducer is an integrated structure formed by connection of an electromagnetic driving device, a low-frequency acoustic excitation device for balancing the static pressure of a liquid medium in a tube and an acoustic measuring cavity. The electromechanical integrated low-frequency acoustic emission energy transducer is simple in structure and convenient to use. Through use of a viscous damper which can move freelyat low-speed relative motion, and can be used as a rigid body at high-speed relative motion, the problem of displacement compensation during static pressurization can be solved, static displacement compensation and transmission of a dynamic force above a certain frequency to a mechanical piston can be achieved, and the electromechanical integrated low-frequency acoustic emission energy transducerhas the advantages of compact structure, excellent performance and convenient use, effectively satisfies requirements for acoustic transmission characteristic testing of pumps and valves, acoustic impedance characteristic testing of pipeline components, and active control of pipeline noise, and also satisfies requirements for testing of acoustic parameters such as acoustic impedance at low frequencies of underwater acoustic materials.

The invention relates to a displacement control method for a hub motor fluid power system variable pump, and belongs to an automobile control system. The revolving speed of front wheels follows the revolving speed of rear wheels. The displacement control method is mainly divided into static regulation and PI (proportional integral) regulation, wherein the static regulation comprises two steps of gear estimation and displacement table search; the table is directly searched according to the estimated gear to obtain a constant value displacement, i.e. the static displacement; the PI feedback regulation of the difference value of the front wheel speed and the rear wheel speed needs to be added to correct the static displacement. The displacement control method for the hub motor fluid power system variable pump has the advantages that the front wheel speed and the rear wheel speed of the automobile can be consistent under the control of the control method when the system is under the auxiliary driving working condition, and the trackslip efficiency of the whole automobile is optimal while the hub motor fluid power system is controlled to obviously improve the passage capacity of the whole automobile on a low-adhering road surface or a road surface with a big slope.

The invention aims to provide a passive vibration isolation device suitable for low frequency vibration. The passive vibration isolation device comprises a device shell and a vibration isolation platform. The device shell comprises a shell body and a shell side body. The shell side body is arranged on the side face of the shell body, a first magnet is installed in the shell side body, a first spring, a second spring and a second magnet are installed in the shell body, the positive pole of the first magnet and the positive pole of the second magnet are opposite, the negative pole of the first magnet and the negative pole of the second magnet are opposite, the upper end of the vibration isolation platform is located outside the shell body, the lower end of the vibration isolation platform is connected with the second magnet, the first spring is arranged between the second magnet and the inner wall of the upper end of the shell body, the vibration isolation platform is sleeved with the first spring, and the second spring is arranged between the second magnet and the inner wall of the lower end of the shell body. The requirements for high static rigidity and low dynamic rigidity can be met, and small static displacement and low frequency vibration isolation performance are guaranteed. Through the device, the influences of foundation vibration and impact on a precise instrument or a driver can be effectively reduced.

The invention relates to a nonlinear seat suspension and a driving seat. The nonlinear seat suspension comprises a suspension body; the suspension body comprises an upper suspension, a vertical suspension and a lower chassis; an elastic compression part correspondingly connected with the upper suspension and the lower chassis is arranged the vertical suspension; cams are arranged on the two sidesof the vertical suspension; a rolling mechanism is arranged on the side surface, far away from the vertical suspension, of each cam; the rolling mechanisms are connected with each other through an elastic stretching part; and horizontal sliding mechanisms are arranged on the side surfaces, far away from the elastic stretching part, of the rolling mechanisms. According to the nonlinear seat suspension, advantages of nonlinear contact, wide vibration isolation frequency band, low static rigidity, high dynamic rigidity and so on can be realized; a situation that the vibration travel and static displacement are large due to a requirement on the low rigidity in the linear suspension moving process is eliminated; the better comfort level is realized; the design is simple.

The invention provides a parameter measuring method and device for a rubber mat for a track. The parameter measuring method for the rubber mat for the track comprises the steps that a static load-static displacement curve of the rubber mat at each of multiple temperatures is obtained, finite element analysis and simulation are performed according to the static load-static displacement curves to obtain the range of dynamic loads capable of being borne by the rubber mat, a dynamic load-dynamic displacement curve of the rubber mat at each of the multiple temperatures is obtained at a second loading rate, dynamic and mechanical features of the rubber mat are obtained according to the dynamic load-dynamic displacement curves, the dynamic and mechanical features are combined with the temperature frequency equivalence principle and the WLF equation, and dynamic and mechanical parameters of the rubber mat at different frequencies at each of the multiple temperatures can be obtained. Compared with the prior art, the defects that measurement of parameters of the rubber mat for the track of the original proportion is not accurate and high in cost can be overcome.

The invention relates to a structural displacement response estimation method and device based on inclination angle monitoring data. The structural displacement response estimation method based on inclination angle monitoring data comprises the following steps: constructing a slope at a node, and establishing a relationship between the slope and an inclination angle at the node; constructing a section node position curve mathematical model; determining a section node position curve according to the relationship between the slope and the inclination angle, the relationship between the slope andthe curve and the monitoring data, wherein the monitoring data comprises an inclination angle at an actual measurement point, the actually measured points are nodes which are provided with inclinometers in the divided sections of the space steel structure and can obtain inclination angle data; and determining the static displacement of the space steel structure according to the section node position curve.

The invention belongs to the field of railway bridge detection, and relates to a method for estimating bridge displacement based on an acceleration sensor. According to the method, the influence of bridge cracks is considered, the damage of a bridge pier is considered with a multi-degree-of-freedom model, and a non-reference displacement estimation method is adopted. The method specifically comprises the following steps that: (1) a finite impulse response filter is applied to avoid displacement drift increased by double integration of acceleration under an uncertain boundary condition, and high-frequency zero-mean-value dynamic displacement is approximately obtained through the filtered acceleration; (2) quasi-static displacement is estimated by using the bending angle of a pier caused by gravity and the projection of the gravity on an acceleration axis; and (3) the high-frequency zero-mean dynamic displacement obtained in the step (1) and the quasi-static displacement obtained in the step (2) are superposed to obtain total estimated displacement. According to the method, the non-reference total displacement of the damaged pier can be estimated under the condition that information is not limited. The method has high precision and achieves measurement of the transverse displacement of the damaged component of a railway bridge.

The invention discloses a real dam displacement monitoring method under the vibration condition. The method comprises steps that, (1), a static displacement monitoring method is employed to measure static dam displacement before vibration and after vibration; (2), during vibration, a dam dynamic acceleration speed is measured through a trigger acceleration gauge, and the acceleration-time function curve is drafted; as the acceleration is second differential of the displacement, second differential calculation of the acceleration-time function curve is carried out to acquire moving displacement; and (3), superposition of the last static displacement before vibration and the moving displacement is carried out to acquire the real dam displacement in the vibration process, the last real dam displacement in the vibration process is taken as the first dam static displacement after vibration, the first dam static displacement is taken as initial amount for subsequent static displacement monitoring, and thereby dam static displacement connection before and after vibration is accomplished. For hydropower stations built in earthquake-prone areas, the method combines a static displacement measurement method in the prior art and a moving displacement measurement method, can completely measure the real dam displacement in 0.1 seconds or even shorter time under the static or vibration conditions and further has properties of high measurement precision, easy popularization and high practical degree.